56 



The sorghums are attacked by several different species of 

 smuts, three of which are widely distributed and destructive. 

 Sphacelotheca Sorghi (Link) Clint, is the covered kernel smut 

 and is to be found wherever sorghums are grown. It is very 

 destructive to the sorghum crop in India and the United States. 

 The flowers are converted into enlarged smut balls; the spores 

 are distributed in harvesting, threshing, and similar operations 

 and contaminate the sound grain. Infection occurs in the 

 seedling stage of the host by means of the seed-borne spores. 

 Sphacelotheca cruenta (Kiihn) Potter is the loose kernel smut 

 of sorghum and seems to be less widely distributed and des- 

 tructive than the covered kernel smut. In this disease the 

 flowers are also converted into enlarged smut balls which break 

 open and allow the escape of the spores. Infection seems to 

 occur mainly by means of spores distributed on the seed. In- 

 fected plants are dwarfed and head out considerably earlier 

 than the sound plants. The third smut is the head smut, 

 Sorosporium Reilianum (Kiihn) McAlpine. It is of special 

 interest because it occurs on both maize and sorghum. It is 

 the maize smut which regularly occurs in Australia. It is com- 

 paratively rare on this crop in the United States. In the head 

 smut, usually the entire head or panicle is converted into a 

 large mass of smut spores. Infection appears to take place 

 mainly by means of spores present in the soil and not from con- 

 taminated seed. 



A large number of varieties of sorghums belonging to the 

 different groups have been tested to determine their suscepti- 

 bility or resistance to the two kernel smuts. Most of the varieties 

 have proved to be highly susceptible to both. There are, 

 however, important exceptions; Feterita, the Milos, Dwarf 

 Brown Kaoliang, as well as a few other varieties, have proved 

 to be markedly resistant to both kernel smuts. The results 

 with both smuts were quite similar, but one striking exception 

 was observed. Darso, which is resistant to Sphacelotheca 

 Sorghi has proved to be quite susceptible to Sph. cruenta. 



The second paper was by Dr. H. A. Gleason, under the title, 

 "Notes on British Guiana Plants". He indicated the parts of 

 British Guiana which had received some botanical exploration 

 and showed that most of this work had been confined to the 

 immediate vicinity of the coast, and that few botanists had 



